Neighbor is two syllables: NEIGH-bor, /ˈneɪbə(r)/, with first-syllable stress. The vowel is the /eɪ/ diphthong. American English shows /ˈneɪbər/. The (r) marks the optional rhotic ending, the British-style form.
Mouth cues
Open the first syllable with your jaw low and your tongue mid, then glide toward the ee position so the mouth tightens into a small smile. That glide is the /eɪ/ sound, the same vowel as day.
Press the /eɪ/ so it stands out and let bor fall away lightly. It is the glide that makes the vowel /eɪ/, not the plain short vowel of bed.
Keep the /b/ gentle between the two syllables, lips closing once, then release straight into the unstressed ending without a pause.
Say it in a phrase
Say the whole phrase smoothly: My neighbor waves every morning. Keep the stress heavy on NEIGH and light on bor, exactly as the target shows.
For a useful contrast, try day beside bed. Day keeps the /eɪ/ diphthong you practiced, while bed uses the plain short /e/ sound, so the pair helps you hear the glide you need in neighbor.
Check yourself with a quick swap: say day, then drop straight into NEIGH-bor. The first vowel should feel identical in both words.